The NEI Central Transgenic Animal Facility is a research support facility for all NEI intramural researchers requiring the use of transgenic mice in their research programs. We are currently providing transgenic animal support to researchers from five laboratories in the NEI (LI, LMDB, LMOD, LRCMB, OGSCB); in our program, there are currently 153 DNA constructs at various stages of completion. NEI researchers using molecular biology techniques to study the eye submit DNA constructs to our section for production of transgenic mice. We create transgenic mice by standard procedures, then biopsy and perform DNA analysis on the mice that are born from these procedures to identify transgene-positive mice. At researchers' request, we mate positive transgenic mice, wean litters, biopsy and analyze DNA from successive generations of transgenic mice, provide the transgenic animals to researchers for use in their experiments, and cryo-preserve and bank embryos from important mouse lines (both transgenic and naturally occurring) for long-term storage.